A Pennsylvania entrepreneur has developed technology that gives you all the battery juice you need directly from the air.
It may sound futuristic, but Powercast's platform uses nothing more complex than a radio--and is cheap enough for just about any company to incorporate into a product. A transmitter plugs into the wall, and a dime-size receiver (the real innovation, costing about $5 to make) can be embedded into any low-voltage device. The receiver turns radio waves into DC electricity, recharging the device's battery at a distance of up to 3 feet.
Picture your cell phone charging up the second you sit down at your desk, and you start to get a sense of the opportunity. How big can it get? "The sky's the limit," says John Shearer, Powercast's founder and CEO. He estimates shipping "many millions of units" by the end of 2008.
For years, electricity experts said this kind of thing couldn't be done. "If you had asked me seven months ago if this was possible, I would have said, 'Are you dreaming? Have you been smoking something?'" says Govi Rao, vice president and general manager of solid-state lighting at Philips (Charts). "But to see it work is just amazing. It could revolutionize what we know about power."